Wonder why? Clues to giraffe’s long neck
Scientists may have figured out why the giraffe is the animal kingdom’s tallest creature. Since Charles Darwin’s speculative evolution theory, scientists have puzzled over how the spotted creature came to have a neck that stretches more than 1.83m long. The answer, according to a study published in Nature Communications, may have to do with a small number of genes that have evolved in the past 11 million to 12 million years, as today’s tallest land mammals split off from their closest relatives. The study, a team effort led by scientists from Pennsylvania State University and the Nelson Mandela Institute of Science and Technology in Tanzania, suggests that the long necks and legs evolved in parallel through changes in 70 genes.
A long neck means that the giraffe is taller and can reach food other animals can’t. It also makes them vulnerable, but the giraffe has come up with some survival tricks. Despite towering at six metres, the giraffe can reach sprints of up to 60 km/h thanks to its sloped back, long legs and short trunk. Then there’s the cardiovascular adaptation. To prevent fainting when they lower their heads to drink water, giraffes have developed an unusually strong pumping mechanism in their hearts that can maintain a blood pressure two and a half times greater than that of humans. The scientists sequenced genomes of two Maasai giraffe and one fetal okapi. The okapi, giraffe’s most closely related species, shares 19.4 per cent of its identical proteins, but not its famously long neck.
Donations: US$5 million for jumbo rescue
Philanthropists and financiers offered more than US$5 million in immediate funding, with pledges of more to come, to launch a series of new elephant protection interventions announced by African presidents at the inaugural Giants Club Summit in Nanyuki. Botswana, Kenya, Uganda and Gabon each laid out visions for actions with proven impact, including new rapid reaction or special operations ranger units, support for strengthening prosecutions, electrified fences to keep elephants out of farmers’ fields, and conservation investment strategies. Kenya will launch a Conservation Endowment Fund.